My general research objectives at the present time are to determine the relationship between structure, function, ontogeny and evolution of hemoglobins and hemocyanins, together with studies of the molecular mechanisms for the control of oxygen transport by these pigments. The immediate specific studies proposed here are directed towards the complete amino acid sequence determination of 1) the constituent polypeptide chains of the high-molecular weight hemoglobin of the earthworm, Lumbricus; 2) component II of Limulus hemocyanin; 3) and the polypeptide chains of certain fish hemoglobins. These studies are directed towards a better understanding of assembly processes in proteins. The large extra-cellular invertebrate pigments from valuable models for the study of assembly, subunit contacts and functional interactions.